U.S. patent application number 15/720471 was filed with the patent office on 2018-05-24 for method and apparatus for bit number allocation and power allocation of subcarriers and electronic equipment.
This patent application is currently assigned to Fujitsu Limited. The applicant listed for this patent is Fujitsu Limited. Invention is credited to Lei Li, Bo Liu.
Application Number | 20180145806 15/720471 |
Document ID | / |
Family ID | 62147371 |
Filed Date | 2018-05-24 |
United States Patent
Application |
20180145806 |
Kind Code |
A1 |
Liu; Bo ; et al. |
May 24, 2018 |
METHOD AND APPARATUS FOR BIT NUMBER ALLOCATION AND POWER ALLOCATION
OF SUBCARRIERS AND ELECTRONIC EQUIPMENT
Abstract
An apparatus and method for bit number allocation and power
allocation of subcarriers and electronic equipment. The apparatus
includes: a bit number calculating unit configured to calculate bit
numbers to which subcarriers in a multicarrier communications
system correspond according to signal to noise ratios of the
subcarriers; a bit number allocating unit configured to allocate
bit numbers for the subcarriers based on the bit numbers to which
the subcarriers correspond calculated by the bit number calculating
unit and a phase noise of the multicarrier communications system in
communicating; wherein, the allocated bit numbers are related to
signal modulation formats of the subcarriers; and a power
allocating unit configured to allocate corresponding power for the
subcarriers according to the bit numbers allocated by the bit
number allocating unit for the subcarriers. With the embodiments, a
transmission performance of the multicarrier communications system
may be improved.
Inventors: |
Liu; Bo; (Beijing, CN)
; Li; Lei; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Fujitsu Limited |
Kawasaki-shi |
|
JP |
|
|
Assignee: |
Fujitsu Limited
Kawasaki-shi
JP
|
Family ID: |
62147371 |
Appl. No.: |
15/720471 |
Filed: |
September 29, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L 27/2626 20130101;
H04W 52/346 20130101; H04L 5/006 20130101; H04W 52/241 20130101;
H04W 36/14 20130101; H04W 36/30 20130101; H04W 52/267 20130101;
H04L 5/0046 20130101; H04W 52/24 20130101 |
International
Class: |
H04L 5/00 20060101
H04L005/00; H04L 27/26 20060101 H04L027/26; H04W 52/24 20060101
H04W052/24; H04W 36/14 20060101 H04W036/14; H04W 36/30 20060101
H04W036/30 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 24, 2016 |
CN |
201611049997.5 |
Claims
1. An apparatus for bit number allocation and power allocation of
subcarriers, including: a bit number calculating unit configured to
calculate carrier bit numbers to which the subcarriers in a
multicarrier communications system correspond according to signal
to noise ratios of the subcarriers; a bit number allocating unit
configured to allocate the carrier bit numbers for the subcarriers
based on the carrier bit numbers to which the subcarriers
correspond calculated by the bit number calculating unit and a
phase noise of the multicarrier communications system in
communicating; wherein, allocated bit numbers are related to signal
modulation formats of the subcarriers; and a power allocating unit
configured to allocate corresponding power for the subcarriers
according to the allocated bit numbers allocated by the bit number
allocating unit for the subcarriers.
2. The apparatus according to claim 1, wherein the bit number
allocating unit includes: a bit number quantizing unit configured
to quantize the carrier bit numbers of the subcarriers calculated
by the bit number allocating unit to obtain integer bit numbers;
and a bit number adjusting unit configured to adjust the integer
bit numbers according to a result of a comparison of the integer
bit numbers with predetermined thresholds set based on a phase
noise, and use adjusted bit numbers as the carrier bit numbers
allocated by the bit number allocating unit.
3. The apparatus according to claim 2, wherein the apparatus
further includes: a threshold setting unit configured to set the
predetermined thresholds according to the phase noise.
4. The apparatus according to claim 3, wherein the threshold
setting unit includes: a calculating subunit configured to,
according to a rotation angle of a constellation induced by the
phase noise and maximum predetermined distances that constellation
points are permitted to move in the constellation to which the
subcarriers correspond, calculate a farthest distance from the
constellation points in the constellation to a center constellation
point; and a setting subunit configured to set the modulation
formats according to a correspondence relationship between the
farthest distance and a modulation format and the farthest
distance, and use corresponding bit numbers to which the set
modulation formats correspond as the predetermined thresholds.
5. The apparatus according to claim 1, wherein the apparatus
further includes: a power adjusting unit configured to adjust the
power allocated by the power allocating unit for the subcarriers
according to the phase noise.
6. The apparatus according to claim 5, wherein, a ratio of power
after adjustment and power before adjustment is: r 1 r 1 - 2 2 R
sin .theta. ; ##EQU00005## where, .theta. denotes the rotation
angle of the constellation of the subcarriers induced by the phase
noise; R denotes the farthest distance from the constellation
points in the constellation to which the subcarriers correspond to
the center; and r.sub.1 denotes a distribution radius of signals
around the constellation points in the constellation before
adjustment.
7. Electronic equipment, including the apparatus for bit number
allocation and power allocation of subcarriers according to claim
1.
8. A method for bit number allocation and power allocation of
subcarriers, including: calculating carrier bit numbers to which
subcarriers in a multicarrier communications system correspond
according to signal to noise ratios of the subcarriers; allocating
carrier bit numbers for the subcarriers based on calculated bit
numbers to which the subcarriers correspond and a phase noise of
the multicarrier communications system in communicating; wherein,
allocated bit numbers are related to signal modulation formats of
the subcarriers; and allocating corresponding power for the
subcarriers according to the allocated bit numbers allocated for
the subcarriers.
9. The method according to claim 8, wherein the allocating bit
numbers for the subcarriers includes: quantizing the calculated bit
numbers of the subcarriers to obtain integer bit numbers; and
adjusting the integer bit numbers according to a result of
comparison of the integer bit numbers with predetermined thresholds
set based on a phase noise, and using the adjusted bit numbers as
the allocated bit numbers.
10. The method according to claim 8, wherein the method further
includes: setting the predetermined thresholds according to the
phase noise.
11. The method according to claim 10, wherein the setting the
predetermined thresholds includes: according to a rotation angle of
a constellation induced by the phase noise and maximum
predetermined distances that constellation points are permitted to
move in the constellation to which the subcarriers correspond,
calculating a farthest distance from the constellation points in
the constellation to a center constellation point; and setting the
modulation formats according to a correspondence relationship
between a farthest distance and a modulation format and the
farthest distance, and using corresponding bit numbers to which the
set modulation formats correspond as the predetermined
thresholds.
12. The method according to claim 8, wherein the method further
includes: adjusting the power allocated for the subcarriers
according to the phase noise.
13. The method according to claim 12, wherein, a ratio of power
after adjustment and power before adjustment is: r 1 r 1 - 2 2 R
sin .theta. ; ##EQU00006## where, .theta. denotes the rotation
angle of the constellation of the subcarriers induced by the phase
noise; R denotes the farthest distance from the constellation
points in the constellation to which the subcarriers correspond to
the center; and r.sub.1 denotes a distribution radius of signals
around the constellation points in the constellation before
adjustment.
14. A non-transitory computer readable storage medium according to
claim 8 for controlling a computer.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Chinese Application
No. 201611049997.5, filed Nov. 24, 2016, in the Chinese
Intellectual Property Office, the disclosure of which is
incorporated herein by reference.
BACKGROUND
1. Field
[0002] This disclosure relates to the field of communications
technologies, and in particular to a method and apparatus for bit
number allocation and power allocation of subcarriers and
electronic equipment.
2. Description of the Related Art
[0003] A multicarrier communications system is a high-efficiency
optical communications system, represented by a discrete multi-tone
(DMT) system. In the multicarrier communications system, it is
often needed to segment a channel into multiple subcarriers for
performing signal transmission.
[0004] In the multicarrier communications system, different bit
numbers may be allocated for the subcarriers according to signal to
noise ratios (SNRs) of the subcarriers, the bit numbers determining
modulation formats of the subcarriers. And according to the
modulation formats of the subcarriers, power may be allocated for
the subcarriers.
[0005] It should be noted that the above description of the
background is merely provided for clear and complete explanation of
this disclosure and for easy understanding by those skilled in the
art. And it should not be understood that the above technical
solution is known to those skilled in the art as it is described in
the background of this disclosure.
SUMMARY
[0006] Additional aspects and/or advantages will be set forth in
part in the description which follows and, in part, will be
apparent from the description, or may be learned by practice of the
embodiments.
[0007] It was found by the inventors of this application that in
the related art, influence of phase noises in the multicarrier
communications system is not taken into account in allocating bit
numbers and power for the subcarriers, hence, transmission
performance of the multicarrier communications system is
degraded.
[0008] Embodiments of this application provide a method and
apparatus for bit number allocation and power allocation of
subcarriers and electronic equipment, in which bit number are
allocated for subcarriers according to phase noises in a
multicarrier communications system, so as to improve transmission
performance of the multicarrier communications system.
[0009] According to a first aspect of the embodiments of this
disclosure, there is provided an apparatus for bit number
allocation and power allocation of subcarriers, including:
[0010] a bit number calculating unit configured to calculate bit
numbers to which subcarriers in a multicarrier communications
system correspond according to signal to noise ratios of the
subcarriers;
[0011] a bit number allocating unit configured to allocate bit
numbers for the subcarriers based on the bit numbers to which the
subcarriers correspond calculated by the bit number calculating
unit and a phase noise of the multicarrier communications system in
communicating; the allocated bit numbers are related to signal
modulation formats of the subcarriers; and
[0012] a power allocating unit configured to allocate corresponding
power for the subcarriers according to the bit numbers allocated by
the bit number allocating unit for the subcarriers.
[0013] According to a second aspect of the embodiments of this
disclosure, there is provided a method for bit number allocation
and power allocation of subcarriers, including:
[0014] calculating bit numbers to which subcarriers in a
multicarrier communications system correspond according to signal
to noise ratios of the subcarriers;
[0015] allocating bit numbers for the subcarriers based on the bit
numbers to which the calculated subcarriers correspond and a phase
noise of the multicarrier communications system in communicating;
the allocated bit numbers are related to signal modulation formats
of the subcarriers; and
[0016] allocating corresponding power for the subcarriers according
to the allocated bit numbers for the subcarriers.
[0017] According to a third aspect of the embodiments of this
disclosure, there is provided electronic equipment, including the
apparatus for bit number allocation and power allocation of
subcarriers as described in the first aspect.
[0018] An advantage of the embodiments of this disclosure exists in
that a transmission performance of the multicarrier communications
system may be improved.
[0019] With reference to the following description and drawings,
the particular embodiments of this disclosure are disclosed in
detail, and the principle of this disclosure and the manners of use
are indicated. It should be understood that the scope of the
embodiments of this disclosure is not limited thereto. The
embodiments of this disclosure contain many alternations,
modifications and equivalents within the scope of the terms of the
appended claims.
[0020] Features that are described and/or illustrated with respect
to one embodiment may be used in the same way or in a similar way
in one or more other embodiments and/or in combination with or
instead of the features of the other embodiments.
[0021] It should be emphasized that the term
"comprises/comprising/includes/including" when used in this
specification is taken to specify the presence of stated features,
integers, steps or components but does not preclude the presence or
addition of one or more other features, integers, steps, components
or groups thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The drawings are included to provide further understanding
of the present disclosure, which constitute a part of the
specification and illustrate the preferred embodiments of the
present disclosure, and are used for setting forth the principles
of the present disclosure together with the description. It is
obvious that the accompanying drawings in the following description
are some embodiments of this disclosure, and for those of ordinary
skills in the art, other accompanying drawings may be obtained
according to these accompanying drawings without making an
inventive effort. In the drawings:
[0023] FIG. 1 is a schematic diagram of the apparatus for bit
number allocation and power allocation of subcarriers of Embodiment
1 of this application;
[0024] FIG. 2 is a schematic diagram of a bit number allocating
unit of Embodiment 1 of this application;
[0025] FIG. 3 is a schematic diagram of distribution of signals
around constellation points before and after being adjusted by a
power adjusting unit of Embodiment 1 of this application;
[0026] FIG. 4 is a schematic diagram of a threshold setting unit of
Embodiment 1 of this application;
[0027] FIG. 5A-5C is a schematic diagram of effects of bit
allocation and power allocation performed by a multicarrier
communications system by respectively using the apparatus of
Embodiment 1 of this application and an apparatus in the related
art;
[0028] FIG. 6 is a flowchart of the method for bit number
allocation and power allocation of subcarriers of Embodiment 2 of
this application;
[0029] FIG. 7 is a flowchart of a method for setting predetermined
thresholds of Embodiment 2 of this application; and
[0030] FIG. 8 is a schematic diagram of the electronic equipment of
Embodiment 3 of this application.
DETAILED DESCRIPTION
[0031] These and further aspects and features of the present
disclosure will be apparent with reference to the following
description and attached drawings. In the description and drawings,
particular embodiments of the disclosure have been disclosed in
detail as being indicative of some of the ways in which the
principles of the disclosure may be employed, but it is understood
that the disclosure is not limited correspondingly in scope.
Rather, the disclosure includes all changes, modifications and
equivalents coming within the terms of the appended claims.
Embodiment 1
[0032] Embodiment 1 of this application provides an apparatus for
bit number allocation and power allocation of subcarriers, used for
performing bit number allocation and power allocation for
subcarriers used by a multicarrier communications system.
[0033] FIG. 1 is a schematic diagram of the apparatus for bit
number allocation and power allocation of subcarriers of Embodiment
1 of this application. As shown in FIG. 1, the apparatus 100
includes a bit number calculating unit 101, a bit number allocating
unit 102 and a power allocating unit 103.
[0034] In this embodiment, the bit number calculating unit 101
calculates bit numbers to which subcarriers in a multicarrier
communications system correspond according to signal to noise
ratios of the subcarriers, the bit number allocating unit 102
allocates bit numbers for the subcarriers based on the bit numbers
to which the subcarriers correspond calculated by the bit number
calculating unit 101 and a phase noise of the multicarrier
communications system in communicating; and, the allocated bit
numbers are related to signal modulation formats of the
subcarriers, and the power allocating unit 103 allocates
corresponding power for the subcarriers according to the bit
numbers allocated by the bit number allocating unit 102 for the
subcarriers.
[0035] With the embodiment of this application, the bit numbers may
be allocated for the subcarriers based on the phase noise in the
multicarrier communications system, thereby improving a
transmission performance of the multicarrier communications
system.
[0036] In this embodiment, the bit number calculating unit 101 may
calculate the bit numbers to which the subcarriers correspond for
the subcarriers according to the SNRs of the subcarriers, and the
bit numbers calculated by bit number calculating unit 101 are often
not integers. The related art may be referred to for calculating
the bit numbers by bit number calculating unit 101, which shall not
be described herein any further.
[0037] FIG. 2 is a schematic diagram of the bit number allocating
unit of this embodiment. As shown in FIG. 2, the bit number
allocating unit 102 may include a bit number quantizing unit 201
and a bit number adjusting unit 202.
[0038] In this embodiment, the bit number quantizing unit 201 is
configured to quantize the bit numbers of the subcarriers
calculated by the bit number allocating unit 101, so as to obtain
integer bit numbers, and the bit number adjusting unit 202 is
configured to adjust the integer bit numbers according to a result
of comparison of the integer bit numbers with predetermined
thresholds set based on a phase noise, and take the adjusted bit
numbers as the bit numbers allocated by the bit number allocating
unit 102.
[0039] In this embodiment, the bit numbers calculated by bit number
calculating unit 101 may be called a first bit number, and the
integer bit number obtained by the bit number quantizing unit 201
may be called a second bit number. The first bit number may not be
integer, while the second bit number is integer.
[0040] In this embodiment, the related art may be referred to for
performing quantization by the bit number quantizing unit 201,
which shall not be described herein any further.
[0041] In this embodiment, the bit number adjusting unit 202 may
adjust the integer bit numbers according to the result of
comparison of the integer bit numbers with the predetermined
thresholds. For example, when the integer bit numbers are greater
than the predetermined thresholds, the bit number adjusting unit
202 may adjust the integer bit numbers into predetermined bit
numbers less than or equal to the predetermined thresholds, and
when the integer bit numbers are less than or equal to the
predetermined thresholds, the bit number adjusting unit 202 may set
the adjusted integer bit numbers to be equal to the integer bit
numbers. Of course, the manner of adjusting by the bit number
adjusting unit 202 is not limited thereto.
[0042] In this embodiment, the power allocating unit 103 may
allocate corresponding power for the subcarriers according to the
bit numbers allocated by the bit number allocating unit 102 for the
subcarriers. The related art may be referred to for a particular
method for allocating power by the power allocating unit 103, which
shall not be described herein any further.
[0043] In this embodiment, as the phase noise of the multicarrier
communications system may cause constellations to which the
subcarriers correspond to rotate with respect to origins of the
constellations, a farthest distance between constellation points of
the constellations to which the subcarriers correspond and centers
may be lowered by adjusting bit numbers of the subcarriers. Hence,
in a case where the constellations are rotated, relatively large
offset of distribution of signals around the constellation points
may be avoided, thereby improving the transmission performance of
the multicarrier communications system.
[0044] In this embodiment, as shown in FIG. 1, the apparatus 100
may further include a power adjusting unit 104 configured to adjust
the power allocated by the power allocating unit 103 for the
subcarriers according to the phase noise.
[0045] FIG. 3 is a schematic diagram of the distribution of signals
around the constellation points before and after being adjusted by
the power adjusting unit 104. As shown in FIG. 3, (A) denotes
distribution of signals around the constellation points before
adjustment, and a range of distribution of signals is: a circle
taking a constellation point 301 as the center and r.sub.1 as the
radius; and (B) denotes distribution of signals around the
constellation points after adjustment, and a range of distribution
of signals is: a circle taking a constellation point 301' as the
center and r.sub.2 as the radius.
[0046] As shown in FIG. 3, r.sub.2 is less than r.sub.1, hence,
even though the constellations are rotated due to the phase noise,
the distribution of signals around the constellation points after
rotation does not go beyond the range of the original circle taking
a constellation point 301 as the center and r.sub.1 as the radius.
Hence, relatively large offset of distribution of signals around
the constellation points may be avoided, thereby improving the
transmission performance of the multicarrier communications
system.
[0047] In this embodiment, as the power allocated for the
subcarriers is inversely proportional to a magnitude of a radius,
power of the subcarriers to which the adjusted constellation points
correspond shown in FIG. 3 is greater than that before adjustment,
that is, by enlarging the power allocated for the subcarriers, the
transmission performance of the multicarrier communications system
may be improved.
[0048] For example, a ratio of the power after adjustment and the
power before adjustment may be expressed by formula (1) below:
r 1 r 1 - 2 2 R sin .theta. ( 1 ) ##EQU00001##
[0049] where, .theta. denotes a rotation angle of the constellation
of the subcarriers induced by the phase noise, and R denotes the
farthest distance from the constellation points in the
constellation to which the subcarriers correspond to the
center.
[0050] In this embodiment, the ratio of the power after adjustment
and the power before adjustment may also be expressed by other
formulae, and this embodiment is not limited to formula (1).
[0051] In this embodiment, as shown in FIG. 1, the apparatus 100
may further include a threshold setting unit 105, which is able to
set the predetermined thresholds used by the bit number adjusting
unit 202 according to the phase noise.
[0052] FIG. 4 is a schematic diagram of the threshold setting unit
105 of this embodiment. As shown in FIG. 4, the threshold setting
unit 105 includes a calculating subunit 401 and a setting subunit
402.
[0053] In this embodiment, according to a rotation angle of a
constellation induced by the phase noise and maximum predetermined
distances constellation points are permitted to move in the
constellation to which the subcarriers correspond, the calculating
subunit 401 may calculate a farthest distance from the
constellation points in the constellation to a center, and the
setting subunit 402 may set the modulation formats according to a
correspondence relationship between a farthest distance and a
modulation format and the farthest distance, and take bit numbers
to which the set modulation formats correspond as the predetermined
thresholds.
[0054] In this embodiment, the calculating subunit 401 may
calculate the farthest distance R from the constellation points in
the current constellation to a center O according to formula (2)
below:
R=d/sin(.theta.) (2).
[0055] (B) in FIG. 3 may be referred to for meanings of the signs
in formula (2); where, .theta. denotes the rotation angle of the
constellation of the subcarriers induced by the phase noise, R
denotes the farthest distance from the constellation points in the
constellation to which the subcarriers correspond to the center O,
and d denotes the maximum predetermined distances constellation
points are permitted to move in the constellation to which the
subcarriers correspond.
[0056] In this embodiment, the setting subunit 402 may acquire the
farthest distance from the constellation points in the
constellation to the center O from a pre-stored list, judge a
modulation format to which the farthest distance corresponds
calculated by the calculating subunit 401, and take the bit number
to which the modulation format corresponds as the predetermined
threshold.
[0057] Furthermore, in this embodiment, the apparatus 100 may not
include the threshold setting unit 104, but may include a storage
portion (not shown), which may store a predetermined list of
correspondence between phase noises and predetermined thresholds.
Hence, the predetermined thresholds may be directly read from the
storage portion.
[0058] With the embodiment of this application, bit numbers may be
allocated for the subcarriers based on the phase noise in the
multicarrier communications system, thereby improving the
transmission performance of the multicarrier communications system.
And furthermore, power may be allocated for the subcarriers based
on the phase noise in the multicarrier communications system,
thereby further improving the transmission performance of the
multicarrier communications system.
[0059] FIG. 5 gives a schematic diagram of effects of bit
allocation and power allocation performed by the multicarrier
communications system by respectively using the apparatus of this
embodiment and an apparatus in the related art. (A), (B) and (C) in
FIG. 5 are respective schematic diagrams of power allocation, bit
number allocation and bit error rates (BERs), of the subcarriers,
in which horizontal axes are indices of the subcarriers, and
vertical axes are the power, bit numbers and BERs, respectively. As
shown in (A) and (B) in FIG. 5, at subcarriers 80-130, the
apparatus of this embodiment allocates higher power and less bit
numbers; and as shown in (C) in FIG. 5, the apparatus of this
embodiment may outstandingly lower the BERs of the subcarriers.
Embodiment 2
[0060] Embodiment 2 of this application provides a method for bit
number allocation and power allocation of subcarriers,
corresponding to the apparatus 100 in Embodiment 1.
[0061] FIG. 6 is a flowchart of the method of this embodiment. As
shown in FIG. 6, the method includes:
[0062] step 601: bit numbers to which subcarriers in a multicarrier
communications system correspond are calculated according to signal
to noise ratios of the subcarriers;
[0063] step 602: bit numbers are allocated for the subcarriers
based on the calculated bit numbers to which the subcarriers
correspond and a phase noise of the multicarrier communications
system in communicating; the allocated bit numbers are related to
signal modulation formats of the subcarriers; and
[0064] step 603: corresponding power is allocated for the
subcarriers according to the bit numbers allocated for the
subcarriers.
[0065] As shown in FIG. 6, the method may further include:
[0066] step 604: the power allocated for the subcarriers is
adjusted according to the phase noise.
[0067] In step 604, a ratio of the power after adjustment and the
power before adjustment may be expressed by formula (1) above.
[0068] As shown in FIG. 6, the method may further include:
[0069] step 605: the predetermined thresholds are set according to
the phase noise.
[0070] FIG. 7 is a flowchart of a method for setting the
predetermined thresholds of this embodiment. As shown in FIG. 7,
the method for setting the predetermined thresholds includes:
[0071] step 701: according to a rotation angle of a constellation
induced by the phase noise and maximum predetermined distances
constellation points are permitted to move in the constellation to
which the subcarriers correspond, a farthest distance from the
constellation points in the constellation to a center is
calculated; and
[0072] step 702: the modulation formats are set according to a
correspondence relationship between a farthest distance and a
modulation format and the farthest distance, and bit numbers to
which the set modulation formats correspond are taken as the
predetermined thresholds.
[0073] With the embodiment of this application, bit numbers may be
allocated for the subcarriers based on the phase noise in the
multicarrier communications system, thereby improving the
transmission performance of the multicarrier communications system.
And furthermore, power may be allocated for the subcarriers based
on the phase noise in the multicarrier communications system,
thereby further improving the transmission performance of the
multicarrier communications system.
Embodiment 3
[0074] Embodiment 3 of this application provides electronic
equipment, including the apparatus for bit number allocation and
power allocation of subcarriers described in Embodiment 1.
[0075] FIG. 8 is a schematic diagram of the electronic equipment of
Embodiment 3 of this application. As shown in FIG. 8, the
electronic equipment 800 may include a central processing unit
(CPU) 801 and a memory 802, the memory 802 being coupled to the
central processing unit 801. For example, the memory 802 may store
various data, and furthermore, it may store a program for
performing bit number allocation and power allocation, and execute
the program under control of the central processing unit 801.
[0076] In an implementation, the functions of the apparatus for bit
number allocation and power allocation of subcarriers may be
integrated into the central processing unit 801.
[0077] The central processing unit 801 may be configured to:
[0078] calculate bit numbers to which subcarriers in a multicarrier
communications system correspond according to signal to noise
ratios of the subcarriers;
[0079] allocate bit numbers for the subcarriers based on the
calculated bit numbers to which the subcarriers correspond and a
phase noise of the multicarrier communications system in
communicating; wherein, the allocated bit numbers are related to
signal modulation formats of the subcarriers; and
[0080] allocate corresponding power for the subcarriers according
to the bit numbers allocated for the subcarriers.
[0081] The central processing unit 801 may further be configured
to:
[0082] quantize the calculated bit numbers of the subcarriers, so
as to obtain integer bit numbers; and
[0083] adjust the integer bit numbers according to a result of
comparison of the integer bit numbers with predetermined thresholds
set based on a phase noise, and take the adjusted bit numbers as
the allocated bit numbers.
[0084] The central processing unit 801 may further be configured
to:
[0085] set the predetermined thresholds according to the phase
noise.
[0086] The central processing unit 801 may further be configured
to:
[0087] according to a rotation angle of a constellation induced by
the phase noise and maximum predetermined distances constellation
points are permitted to move in the constellation to which the
subcarriers correspond, calculate a farthest distance from the
constellation points in the constellation to a center; and
[0088] set the modulation formats according to a correspondence
relationship between a farthest distance and a modulation format
and the farthest distance, and take bit numbers to which the set
modulation formats correspond as the predetermined thresholds.
[0089] The central processing unit 801 may further be configured
to:
[0090] adjust the power allocated by the power allocating unit for
the subcarriers according to the phase noise.
[0091] The central processing unit 801 may further be configured
to:
[0092] a ratio of power after adjustment and power before
adjustment is:
r 1 r 1 - 2 2 R sin .theta. ; ##EQU00002##
[0093] where, .theta. denotes the rotation angle of the
constellation of the subcarriers induced by the phase noise, R
denotes the farthest distance from the constellation points in the
constellation to which the subcarriers correspond to the center,
and r.sub.1 denotes a distribution radius of signals around the
constellation points in the constellation before adjustment.
[0094] Furthermore, as shown in FIG. 8, the electronic equipment
800 may include an input/output unit 803, and a display unit 804,
etc. Functions of the above components are similar to those in the
related art, and shall not be described herein any further. It
should be noted that the electronic equipment 800 does not
necessarily include all the parts shown in FIG. 8, and furthermore,
the electronic equipment 800 may include parts not shown in FIG. 8,
and the related art may be referred to.
[0095] An embodiment of the present disclosure further provides a
computer readable program code, which, when executed in an
apparatus for bit number allocation and power allocation of
subcarriers or electronic equipment, will cause the apparatus or
the electronic equipment to carry out the method for bit number
allocation and power allocation of subcarriers described in
Embodiment 2.
[0096] An embodiment of the present disclosure provides a computer
readable medium, including a computer readable program code, which
will cause an apparatus for bit number allocation and power
allocation of subcarriers or electronic equipment to carry out the
method for bit number allocation and power allocation of
subcarriers described in Embodiment 2.
[0097] The apparatus for bit number allocation and power allocation
of subcarriers described with reference to the embodiments of this
disclosure may be directly embodied as hardware, software modules
executed by a processor, or a combination thereof. For example, one
or more functional block diagrams and/or one or more combinations
of the functional block diagrams shown in FIGS. 1-2 may either
correspond to software modules of procedures of a computer program,
or correspond to hardware modules. Such software modules may
respectively correspond to the steps described in Embodiment 2. And
the hardware module, for example, may be carried out by firming the
soft modules by using a field programmable gate array (FPGA).
[0098] The soft modules may be located in an RAM, a flash memory,
an ROM, an EPROM, and EEPROM, a register, a hard disc, a floppy
disc, a CD-ROM, or any non-transitory computer readable storage or
memory medium in other forms known in the art. A memory medium may
be coupled to a processor, so that the processor may be able to
read information from the memory medium, and write information into
the memory medium; or the memory medium may be a component of the
processor. The processor and the memory medium may be located in an
ASIC. The soft modules may be stored in a memory of a mobile
terminal, and may also be stored in a memory card of a pluggable
mobile terminal. For example, if equipment (such as a mobile
terminal) employs an MEGA-SIM card of a relatively large capacity
or a flash memory device of a large capacity, the soft modules may
be stored in the MEGA-SIM card or the flash memory device of a
large capacity.
[0099] One or more functional blocks and/or one or more
combinations of the functional blocks in FIGS. 1-2 may be realized
as a universal processor, a digital signal processor (DSP), an
application-specific integrated circuit (ASIC), a field
programmable gate array (FPGA) or other programmable logic devices,
discrete gate or transistor logic devices, discrete hardware
component or any appropriate combinations thereof carrying out the
functions described in this application. And the one or more
functional block diagrams and/or one or more combinations of the
functional block diagrams shown in FIGS. 1-2 may also be realized
as a combination of computing equipment, such as a combination of a
DSP and a microprocessor, multiple processors, one or more
microprocessors in communications combination with a DSP, or any
other such configuration.
[0100] This disclosure is described above with reference to
particular embodiments. However, it should be understood by those
skilled in the art that such a description is illustrative only,
and not intended to limit the protection scope of the present
disclosure. Various variants and modifications may be made by those
skilled in the art according to the principle of the present
disclosure, and such variants and modifications fall within the
scope of the present disclosure.
[0101] For implementations of the present disclosure containing the
above embodiments, following supplements are further disclosed.
[0102] Supplement 1. An apparatus for bit number allocation and
power allocation of subcarriers, including:
[0103] a bit number calculating unit configured to calculate bit
numbers to which subcarriers in a multicarrier communications
system correspond according to signal to noise ratios of the
subcarriers;
[0104] a bit number allocating unit configured to allocate bit
numbers for the subcarriers based on the bit numbers to which the
subcarriers correspond calculated by the bit number calculating
unit and a phase noise of the multicarrier communications system in
communicating; wherein, the allocated bit numbers are related to
signal modulation formats of the subcarriers; and
[0105] a power allocating unit configured to allocate corresponding
power for the subcarriers according to the bit numbers allocated by
the bit number allocating unit for the subcarriers.
[0106] Supplement 2. The apparatus according to supplement 1,
wherein the bit number allocating unit includes:
[0107] a bit number quantizing unit configured to quantize the bit
numbers of the subcarriers calculated by the bit number allocating
unit, so as to obtain integer bit numbers; and
[0108] a bit number adjusting unit configured to adjust the integer
bit numbers according to a result of comparison of the integer bit
numbers with predetermined thresholds set based on a phase noise,
and take the adjusted bit numbers as the bit numbers allocated by
the bit number allocating unit.
[0109] Supplement 3. The apparatus according to supplement 2,
wherein the apparatus further includes:
[0110] a threshold setting unit configured to set the predetermined
thresholds according to the phase noise.
[0111] Supplement 4. The apparatus according to supplement 3,
wherein the threshold setting unit includes:
[0112] a calculating subunit configured to, according to a rotation
angle of a constellation induced by the phase noise and maximum
predetermined distances that constellation points are permitted to
move in the constellation to which the subcarriers correspond,
calculate a farthest distance from the constellation points in the
constellation to a center; and
[0113] a setting subunit configured to set the modulation formats
according to a correspondence relationship between a farthest
distance and a modulation format and the farthest distance, and
take bit numbers to which the set modulation formats correspond as
the predetermined thresholds.
[0114] Supplement 5. The apparatus according to supplement 1,
wherein the apparatus further includes:
[0115] a power adjusting unit configured to adjust the power
allocated by the power allocating unit for the subcarriers
according to the phase noise.
[0116] Supplement 6. The apparatus according to supplement 5,
wherein,
[0117] a ratio of power after adjustment and power before
adjustment is:
r 1 r 1 - 2 2 R sin .theta. ; ##EQU00003##
[0118] where, .theta. denotes the rotation angle of the
constellation of the subcarriers induced by the phase noise;
[0119] R denotes the farthest distance from the constellation
points in the constellation to which the subcarriers correspond to
the center;
[0120] and r.sub.1 denotes a distribution radius of signals around
the constellation points in the constellation before
adjustment.
[0121] Supplement 7. Electronic equipment, including the apparatus
for bit number allocation and power allocation of subcarriers as
described in any one of supplements 1-6.
[0122] Supplement 8. A method for bit number allocation and power
allocation of subcarriers, including:
[0123] calculating bit numbers to which subcarriers in a
multicarrier communications system correspond according to signal
to noise ratios of the subcarriers;
[0124] allocating bit numbers for the subcarriers based on the
calculated bit numbers to which the subcarriers correspond and a
phase noise of the multicarrier communications system in
communicating; wherein, the allocated bit numbers are related to
signal modulation formats of the subcarriers; and
[0125] allocating corresponding power for the subcarriers according
to the bit numbers allocated for the subcarriers.
[0126] Supplement 9. The method according to supplement 8, wherein
the allocating bit numbers for the subcarriers includes:
[0127] quantizing the calculated bit numbers of the subcarriers, so
as to obtain integer bit numbers; and
[0128] adjusting the bit numbers according to a result of
comparison of the integer bit numbers with predetermined thresholds
set based on a phase noise, and taking the adjusted bit numbers as
the allocated bit numbers.
[0129] Supplement 10. The method according to supplement 8, wherein
the method further includes:
[0130] setting the predetermined thresholds according to the phase
noise.
[0131] Supplement 11. The method according to supplement 10,
wherein the setting the predetermined thresholds includes:
[0132] according to a rotation angle of a constellation induced by
the phase noise and maximum predetermined distances that
constellation points are permitted to move in the constellation to
which the subcarriers correspond, calculating a farthest distance
from the constellation points in the constellation to a center;
and
[0133] setting the modulation formats according to a correspondence
relationship between a farthest distance and a modulation format
and the farthest distance, and taking bit numbers to which the set
modulation formats correspond as the predetermined thresholds.
[0134] Supplement 12. The method according to supplement 8, wherein
the method further includes:
[0135] adjusting the power allocated for the subcarriers according
to the phase noise.
[0136] Supplement 13. The method according to supplement 12,
wherein,
[0137] a ratio of power after adjustment and power before
adjustment is:
r 1 r 1 - 2 2 R sin .theta. ; ##EQU00004##
[0138] where, .theta. denotes the rotation angle of the
constellation of the subcarriers induced by the phase noise;
[0139] R denotes the farthest distance from the constellation
points in the constellation to which the subcarriers correspond to
the center;
[0140] and r.sub.1 denotes a distribution radius of signals around
the constellation points in the constellation before
adjustment.
[0141] Although a few embodiments have been shown and described, it
would be appreciated by those skilled in the art that changes may
be made in these embodiments without departing from the principles
and spirit thereof, the scope of which is defined in the claims and
their equivalents.
* * * * *